Itea virginica

The gardens of America would be better sites with more use of Itea virginica, sweetspire.

Forget that this shrub is highly adaptable and surprisingly drought tolerant for a native of moist soil. Sweetspire has the double benefit of fragrant, summer flowers and dazzling, autumn color.

Actually, it's not really fair to call it autumn color. Sweetspire's late-season red foliage can last through the winter in warmer areas like USDA Hardiness Zone 9. Even in cooler zones, red leaves persist often until December or as long as winter temperatures don't dip below 15F-20F. University of Georgia horticulturist Mike Dirr observed that I. virginica can retain some fall-color foliage until temperatures drop to minus 3F.

You'll see this beautiful late-season display on a shrub with a sometimes gangly form. Native to moist, understory areas near creeks, sweetspire naturally has a leggier, often uneven growth habit. The plant can produce denser and neater foliage and branches with a sunnier site, pruning and fertilization.

Though sweetspire is native to moist areas, it has been reported as significantly drought tolerant. It can establish in a landscape with only one year of supplemental watering.

Stop to smell the flowers

The fragrant flowers that give sweetspire its name are white, 1/3-1/2 inch in diameter, upright and clustered on 6-inch racemes that abundantly cover the shrub. Flowers are replaced by five-valved, capsuled fruit that is 1/4-1/3 inch long.

Leaves are simple, alternate, oblong to almost linear. The leaf top is dark green and smooth; the leaf bottom appears lighter because it is covered with fine hairs. Fall color can range from true red to red-orange.

The shrub's bark is brown or gray and forms scales with age. Young stems are smooth and green. It typically grows to be 3-5 feet tall with a width greater than its height, but some specimens have grown to 10 feet.

Sweetspire transplants easily from containers. For a larger shrub, the plant can be divided at the roots and replanted separately. Plants in the landscape that are not pruned will mound and spread into a thicket.

Four propagation options

I. virginica grows wild from New Jersey to East Texas. It seems highly adaptable to varying pH levels and has no serious pests. It can be propagated by hardwood cuttings, softwood cuttings, division or seed.

Sweetspire will grow from softwood cuttings with or without an indolebutyric acid treatment, but a quick dip in 3,000 parts per million IBA nearly ensures 100-percent rooting. Cuttings need about four weeks to root.

Sweetspire seeds are also quick to grow and require no pretreatment. One of the most popular cultivars to produce is 'Henry's Garnet.' This cultivar was selected at Swarthmore College because it showed beautiful, 6-inch racemes and brilliant reddish-purple fall color. Its typical habit is 3-4 feet tall and 4 1/2-6 feet wide. It is cold hardy to minus 20F and roots readily from softwood cuttings.

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Specifics

Name: Itea virginica

Common name: Sweetspire.

Family: Saxifragaceae.

Description: Semi-evergreen or evergreen shrub that grows 3-10 feet tall and has a greater width than height. Deep-green leaves change to brilliant red or red-orange in fall and hold until December or later. Native to moist soils from New Jersey to East Texas.

Hardiness: USDA Hardiness Zones 5-9.

Diseases/pests: None significant.

Landscape value: Fragrant, summer flowers; striking fall foliage.

Consumer benefit: Sweetspire is an ornamental, semi-evergreen/evergreen shrub that can easily adapt to many garden conditions.

Grower benefits: Adapts well to container or field production; growth rate is medium to fast, especially with proper nutrition.

- Holly Cuny